meta-google: dropbear: Allow for DEV builds

Change-Id: I73cf1b4f0777080521180352124f6c271fab2815
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-core/dropbear/dropbear_%.bbappend b/meta-google/recipes-core/dropbear/dropbear_%.bbappend
new file mode 100644
index 0000000..20c53fe
--- /dev/null
+++ b/meta-google/recipes-core/dropbear/dropbear_%.bbappend
@@ -0,0 +1,11 @@
+# Allow SSH to the mgmt node on DEV builds
+do_install_append_gbmc_dev() {
+  nftables_dir=${D}${sysconfdir}/nftables
+  rules=$nftables_dir/50-dropbear-dev.rules
+  install -d -m0755 $nftables_dir
+  echo 'table inet filter {' >"$rules"
+  echo '    chain mgmt_pub_input {' >>"$rules"
+  echo '        tcp dport 22 accept' >>"$rules"
+  echo '    }' >>"$rules"
+  echo '}' >>"$rules"
+}